Thermal processing apparatuses are used to perform thermal processing on various substrates such as semiconductor substrates, substrates for liquid crystal displays, substrates for plasma displays, substrates for optical disks, substrates for magnetic disks, substrates for magneto-optical disks or substrates for photomasks.
A substrate cooling apparatus described in Patent Document 1 has a temperature setter and a cooling plate. The cooling plate includes a heat conduction plate and Peltier elements. A high-temperature substrate before cooling processing is carried to the heat conduction plate. A substrate cooling target temperature and an initial temperature of the heat conduction plate are set in the temperature setter. The initial temperature of the heat conduction plate is not higher than the substrate cooling target temperature.
The heat conduction plate is controlled to be at the set initial temperature until the substrate is carried to the heat conduction plate. When the high-temperature substrate is carried to the heat conduction plate, the heat conduction plate and the substrate are cooled at maximum capacity by the Peltier elements. The cooling at maximum capacity by the Peltier element refers to cooling by driving the Peltier elements with their maximum capacity without adjusting an increase or a decrease of a degree to which cooling is performed depending on outputs of a temperature sensor for the substrate and a temperature sensor for the heat conduction plate.
When the substrate temperature has reached the set substrate cooling target temperature, the substrate is moved to be apart from the cooling plate to a position at which the substrate is not affected by heat generated by the heat conduction plate. Thus, the cooling processing on the substrate is completed. After that, the temperature of the heat conduction plate is restored to the initial temperature in preparation for cooling processing for a subsequent substrate.
[Patent Document 1] JP 7-115058 A